Half-Hole Impedance PCB

A 6-layer half-hole PCB with controlled impedance on S1141 mid-Tg laminate, 1.2±0.12mm thick, with 0.635mm half-hole diameter. Half holes (also called castellations) are PTHs cut in half along the board edge during routing, leaving a half-cylinder of plated copper that lets the PCB act as a surface-mount module — solder flows up the half-hole onto the carrier board, replacing connectors and saving height. Combined with controlled-impedance routing for high-speed differential signals, the board fits SMT-mount RF modules, Wi-Fi/Bluetooth/Zigbee modems, and 5G NB-IoT modules where consistent characteristic impedance and low reflection matter. Sihui Fuji controls the routing process to prevent copper lift and plating shedding at the half-hole edge. Used in IoT modules, wearable RF subsystems, consumer wireless, and telecom modules.